I love to use keyboard shortcuts to speed up my everyday workflow. Chromebooks have many of the same shortcuts as Windows and Mac (copy, cut, paste, print etc), but here are some that are OS specific.
Show Chrome OS version at login screen :: ALT + V
Set screen resolution to default :: CTRL + SHIFT + 0
Lock screen :: CTRL + SHIFT + L
Log out :: CTRL + SHIFT + Q
Toggle Caps lock :: ALT + SearchButton
Launch Task Manager :: SearchButton + ESC
Show all keyboard shortcuts :: CTRL + ALT + ?